I made a scenario in Fall from Heaven called Against the Wall that tried to use that. You played as the Dwarven Khazad that had to build and hold 5 cities for at lease 100 turns against more mobile Hippus horseman whose waves got more powerful over time. It never quite felt right. I think because so much of what makes 4x great is that explore and exploit aspect that that model minimized.

Sorcerer King does a much better job of it with it's outposts firing at enemies that come to close and the Sorcerer King sending waves at you if you make him angry. I think it feels better because you still get keep the exploration side of the game, and a lot of the strategic depth comes from balancing out that defensive side with wanting to get out into the world to search and find goodies.

Another question, what 4x has the best diplomacy?

as to answer diplomacy medieval total war, but I haven't. Played a lot if games wish list.

1. Customization.

2. Lots of options.

3. Lots of players.

4. Big

5. Unbeatable. Never get bored because Ai is to easy.

6. Harder levels mean harder not handicapped.

7. I don't. Want anything the Ai can't. Use as far as exploits goes.

8. I don't want mechanics I don't have to work to achieve is economic gc2 good.

9. Spore being actually a game. Compare to sins what's missing from spore a game. Empire earth.

10. Games to pay attention to competition. Ie spore didn't pay attention to competition acted more like a Sega genesis game than 2008 game.

11. Tech researching.

12. Strategy.

13. Not all automation.

14. Good diplomacy.

15. Good game editor.

16. Support for features is galactic civilazations good mods poor downloadable.

This is a great list.

To your "not all automation" point, I was listening to Fred Ford and Paul Reiche (creators of Star Control and Star Control II) talk about their design (these guys are brillant btw), and they said something that stuck with me. Apparently early on in Star Control you could set your crew to go explore planets for resources. You would send them out, and then you would get the results on whatever they found. This was fine, but got so much better when the players could actually go explore the planets themselves. The rule they came up with was "Don't ever do something for the player if its fun for the player to do himself."  I think that's the magic line. try to make all the interactions in a game fun, if they can't be, then automate them, but don't automate out fun activities.

If I am reading your number 7 correctly, I assume you mean that you don't want mechanics in the game that you don't need to use to win. If I am understanding you correctly then I tend to lean the other way on that one. I like ancillary systems that more casual players can ignore but the hard core can dig into to be more efficient. An example would be the great person system in Civilization IV. All casual players know is that everyone and a while they get a great person they can do fun things with. Where a hard core player can manage and work that system for better results. You could make the same argument about the ship designer in Galactic Civilizations III, where at the highest level you never need to use it. The midcore can go in and design their own ships with the components they want and the hard core can make amazing and beautiful creations.

I do agree that having neutered systems that don't do much, or don't do much relative to the time put into them is bad. I don't want to spend 30 minutes fighting a tactical battle if winning the overall war has little to do with those tactical battle decisions. I don't want to spend a bunch of time gathering components to craft items if those items are weak.

Not sure if this thread is still active, but there are two features I've been waiting for for ages:

1. Multiple plains that can be used strategically (rather than just being different areas connected by portals). The Midgard scenario back in Civ2:ToT did this well - by searching for tunnels in the underground layer you would be able to travel between continents before learning to build ships, or were able to get inside otherwise inaccessible areas (surrounded by impassable terrain). The sky layer was also interesting, though I would have gone with floating islands (rather than solid clouds) and have given units standing on these increased vision of the land below - they could be used as outposts to increase sight beyond borders.

2. Dynamic "rising" of minor civs. It has always bugged me in games like Endless Legend that some races will always be major empires (the playable races), while others are content to live in single villages for eternity. I'd imagined some kind of system where all civs start of as minor, and various events through the course of the game lead to some developing into empires with larger ambitions. These triggers could be threats (proximity to a larger hostile civ, they see it as a way of defending themselves) or random (a new heir to the throne has higher ambitions than his predecessor). A number of these conversions would be forced early game to provide the player with rivals, but some would continue to happen later game also. Similarly, a largely defeated civ retaining only a single city or two may choose to remove itself from the struggle for domination and return to minor-civ status.

Of course, the other thing I'm waiting for is a return of the lore and setting from FFH... I think the races and backstory from the Elemental universe are one of its weakest points.